1. Field of the Invention
The invention relates to an electrical terminal with a clamping spring, with a metal part and with a housing which holds the clamping spring and the metal part and which has at least one conductor insertion opening, the clamping spring having a clamping leg, an actuating leg, and a back which connects the two legs to one another, the clamping leg with the metal part forming a clamping site for a stripped conductor which is to be connected, the clamping spring being supported to be able to pivot in the housing or on the metal part such that the clamping spring can be moved out of a first (opened) position into a second (closed) position, and a stripped electrical conductor which has been inserted through the conductor insertion opening in the first position of the clamping spring being insertable into the clamping site, without the clamping leg having to be deflected against its spring force, and in the second position of the clamping spring being clamped in an electrically conductive manner between the end of the clamping leg and the metal part.
2. Description of Related Art
Electrical terminals are known in a plurality of embodiments. Terminals can be made, for example, for connection of an electrical conductor to a circuit board as a so-called print terminal or for connection to another conductor as a terminal block. The clamping springs are both loop-shaped clamping springs, so-called tension spring terminals, as well as U-shaped or V-shaped clamping springs, so-called leg springs, into which rigid conductors or conductors provided with one ferrule can be directly inserted, i.e. without the clamping site needing to be opened beforehand with a tool. In the known loop-shaped tension springs, according to their name, the conductor which is to be connected is pulled against a busbar by the clamping leg. In contrast, for U-shaped or V-shaped clamping springs the conductor to be connected is pressed by the clamping leg against the busbar or one region of the metal part.
To actuate the tension spring terminal, an actuating tool, for example, a screw driver, is necessary which is inserted into an actuating shaft to open the terminal. In doing so, the tip of the screwdriver tensions the tension spring, as a result of which the clamping site opens. A conductor which is to be connected can be inserted into the clamping leg through a recess and is clamped against a busbar connected to the tension spring by the lower edge of the recess after the actuating tool is removed. Here, terminals are also known in which an actuating element is located in the housing in order to facilitate the opening of the tension spring terminal. This terminal, with an actuating thrustor, is known, for example, from German Patent Application DE 10 2007 009 082 A1 and corresponding to U.S. Pat. No. 7,438,587 B2.
German Utility Model DE 203 13 041 U1 discloses an electrical terminal with an essentially U-shaped clamping spring and a metal part. In this terminal, the clamping spring, which can also be called a leg spring, acts as a compression spring which presses a conductor to be connected against a contact element or a busbar by the spring force of the clamping spring and as a result establishes the electrically conductive contact between the conductor and the contact element or the busbar.
These terminals are also called edge socket terminals since they enable the insertion of a rigid conductor or a conductor which is provided with a ferrule into the clamping site without the clamping site having to be opened with an actuating tool (see, brochure “Series terminals CLIPLINE 2005, Page 20 from Phoenix Contact GmbH & Co. KG). Here, the clamping leg is deflected against its spring force by the insertion of the conductor; the insertion of the conductor is thus associated with a certain expenditure of force. In doing so, a compromise must always be found between a high spring force which is desirable for good electrical contact-making on the one hand and a low spring force of the clamping leg which facilitates insertion of the conductor, on the other.
The initially described electrical terminal is known from German Patent Application DE 196 13 557 A1. In this terminal, the clamping spring is pivotally arranged in the U-shaped metal part, for which the clamping spring in the region of the back has two lateral projections which are supported in the corresponding receivers in the U-legs of the metal part. The terminal which is known from German Patent Application DE 196 13 557 A1 has the advantage that the shorter first leg of the clamping spring which acts as the clamping leg when the stripped conductor which is to be connected is being inserted need not be deflected against its spring force so that even a flexible conductor can be inserted into the electrical terminal without using a tool. The disadvantage in this electrical terminal is, however, that the actuation of the clamping spring is relatively tedious, especially when the terminal has relatively small dimensions.
Since, to open the clamping site, it is moreover necessary for the end of the actuating leg to be freely accessible so that the end can be actuated by hand, there is the danger that the mechanic will injure himself on the end of the clamping spring which projects out of the housing. This danger prevails especially when the clamping spring is made of metal since then the end of the actuating leg projecting out of the housing is connected in an electrically conductive manner to the connected conductor.